Some time ago i bought 5 red laser diodes which are in a cylinder with 18mm diameter which holds the diode and collimator with lens.
It came to my thought to use these 4 x 150 mw to make a simple quad setup with a pbs cube.
Since i don't have materials/expertise to create something to hold the modules in place i got a tip from a friend who pointed me to here they have special pipe holders from 6 to very 58 or so mm. I got 4 sets of module holders, all together, for 12 euros.

Here are the items.
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There is also a baseplate that is a little larger with two mounting holes, i got those with the set.
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